This invention relates to a valve timing control apparatus and a variable valve actuating apparatus for an internal combustion engine which are configured to control an opening timing and a closing timing of, for example, an intake valve and an exhaust valve.
Japanese Patent Application Publication No. 2011-226372 (corresponding to U.S. Patent Application Publication No. 2011/253085) discloses a valve timing control apparatus for an internal combustion engine including a cover member which is provided on an front end side of a motor housing of an electric motor with a predetermined clearance. A pair of slip rings confronting the clearance is fixed on an inner surface of the cover member. A power feeding plate is fixed at a front end portion of the motor housing. A power feeding brush is provided to the power feeding plate. The power feeding brush is arranged to be slidably abutted on the slip ring, and thereby to feed the power to a coil of the electric motor.
A rotation sensing mechanism of an electromagnetic induction type is provided between one end portion of a motor output shaft of the electric motor which is on the cover member's side, and the cover member confronting the one end portion of the motor output shaft of the electric motor in the axial direction. The rotation sensing mechanism is arranged to sense a rotation angle of the motor output shaft.
This rotation sensing mechanism includes a sensed rotor fixed to one end portion of the motor output shaft; and a sensing portion provided to confront a tip end portion of the sensed rotor of the cover member. This sensing portion confronts the tip end portion of the sensed rotor with a predetermined gap.